Two possibilities...
If these are sour cherries, they may not require any acid. If the pH is below 3.0 (if I remember) then the yeast may have a hard time starting. You also did not mention the starting gravity (SG).
A yeast starter is highly recommended. It enables the yeast colony to greatly multiply before being thrown into the hostile environment of low pH or high sugar.
So...
Do you have pH strips and can measure pH? If not then taste, is it mouth puckering?
Do you have a hydrometer to measure the SG?
If it were mine I would make a yeast starter with another packet of yeast right now, add 1 TBS of sugar, and 1 tsp of Go-Ferment. If the wine shows no sign of starting, then take your yeast starter, tomorrow, and add it to the wine. So to be clear, a yeast starter works best when it has 12-24 hours to work. That’s why you start it now, then decide 24 hours from now if your wine has started or not and add it then.